1. Field of the Invention
This invention relates to a serial ink jet printer for supplying ink from an ink supply section at a fixed position to an ink jet head mounted on a carriage, moving the carriage in a print width direction, and printing on a recording medium passing through a print position. More particularly, the invention relates to a serial ink jet printer that includes a detection mechanism for detecting, among other things, the presence or absence of ink in an ink supply section and the move position of a carriage in the serial ink jet printer.
2. Related Art
Known as an ink jet printer is a serial ink jet printer for reciprocating a carriage on which an ink jet head is mounted in the print width direction of a transported recording paper and printing on a predetermined surface of the recording paper. As the serial ink jet printer, an off-carriage type serial ink jet printer is available, wherein an ink supply section such as an ink cartridge is not mounted on a carriage, but rather is placed at a fixed position and ink is supplied from the ink supply section via a flexible ink tube to an ink jet head mounted on the carriage.
In the off-carriage type serial ink jet printer, a plurality of ink tanks storing different color inks, for example, a plurality of ink cartridges, are placed in the ink supply section to perform multicolor print. In this case, it is necessary to detect the ink cartridges being placed in the ink supply section and the presence or absence of ink in each ink cartridge. To do this, in the related art, a dedicated detection mechanism for detecting each ink cartridge being placed and a dedicated detection mechanism for detecting the presence or absence of ink are used. Generally, each detection mechanism is made up of an optical detector, etc., and a detected part detected by the detector.
Further, in the serial ink jet printer of the related art, to control the move position of the carriage, a detection mechanism for detecting the home position of the carriage as the reference for controlling the move position of the carriage is used.
Therefore, for example, if the serial ink jet printer comprises the ink supply section in which two ink cartridges are placed, two detection mechanisms for detecting the presence or absence of the ink cartridges, two detection mechanisms for detecting the presence or absence of ink in the ink cartridges, and one detection mechanism for detecting the carriage home position (five detection mechanisms in total) are required.
Also known in the related art is a serial ink jet printer wherein an ink supply section can be switched between a single-color cartridge and a multicolor cartridge for use, and both single-color print and multicolor print can be performed. In this serial ink jet printer, single-color print or multicolor print is specified by operating a DIP switch, etc., installed on a printer controller.
However, to detect the presence or absence of each ink cartridge, the presence or absence of ink in the cartridges, and the carriage home position by separate detection mechanisms as in the related art, the number of the detection mechanisms increases, which in turn increases the costs and inhibits miniaturization of this type of ink jet printer.
With the serial ink jet printer wherein single-color print or multicolor print is specified by operating a DIP switch, etc., when the user forgets to switch the DIP switch, etc., a single-color print may be executed although the user intends to execute multicolor print and vice versa, for example.
It is therefore an object of the invention to make it possible to determine information concerning an ink supply section such as the presence or absence of ink, information concerning the move position of the carriage such as a home position of a carriage, and whether the print mode is single-color print or multicolor print by a fewer number of detection mechanisms in an off-carriage type serial ink jet printer.
To this end, according to the invention, there is provided an ink jet printer comprising an ink jet head, a carriage for moving the ink jet head in a print width direction, an ink supply section placed at a fixed position for supplying ink to the ink jet head, and a detector and one or more detected parts that can be detected by the detector, wherein the one or more detected parts are placed at a position along a move passage of the detector, and the one or more detected parts are operable to indicate at least one of information concerning the ink supply section and information concerning the move position of the carriage.
In the invention, the detector is mounted on the carriage and is moved together with the carriage for detecting the one or more detected parts. Therefore, if a plurality of detected parts are placed, the detector for detecting the detected parts can be made common. Thus, the invention is advantageous for cost reduction and miniaturization as compared with the detection system comprising detectors and detected parts provided in a one-to-one correspondence with the objects to be detected as in the related art.
In the invention, the information concerning the ink supply section may be, for example, at least one of information indicating whether or not ink exists in the ink supply section and information representing the type of ink stored in the ink supply section.
In addition, the information concerning the move position of the carriage may include information indicating whether or not the carriage is at the home position, etc.
Generally, as the one or more detected parts, a first detected part that can indicate the information concerning the ink supply section and a second detected part that can indicate the information concerning the move position of the carriage may be used.
The detector can be an optical detector comprising a light emission element and a light reception element. In this case, the one or more detected parts can each include a prism having one or more reflection faces for reflecting light from the light emission element toward the light reception element.
If the one or more detected parts indicate the information concerning the ink supply section, the corresponding prism may be formed in a side wall portion of an ink reservoir of the ink supply section. In doing so, if ink exists in the ink reservoir, the back of the one or more reflection faces of the corresponding prism are immersed in the ink and thus the one or more reflection faces do not function as a reflection face and therefore the detector does not detect reflected light. In contrast, if the ink reservoir becomes empty of ink, the one or more reflection faces of the corresponding prism are exposed from the ink and function as reflection faces and therefore the detector detects reflected light. Thus, the presence or absence of ink can be detected based on the presence or absence of reflected light.
To determine the type of ink stored in the ink supply section, the one or more reflection faces need to be made effective regardless of the presence or absence of ink. To do this, one or more of the detected parts may comprise a gap formed between the one or more reflection faces of a corresponding prism and the side wall portion opposed thereto on an opposite side to the light incidence direction from the detector on the corresponding prism. The one or more reflection faces are made effective regardless of the presence or absence of ink in the presence of the gap.
Next, the ink supply section may be a cartridge type having an ink cartridge placement section and an ink cartridge detachably placed therein.
In this embodiment, like above, if the one or more detected parts can indicate the information concerning the ink supply section, the information concerning the ink supply section can be at least one of information indicating whether or not the ink cartridge is placed in the ink cartridge placement section, information concerning the type of placed ink cartridge, and information indicating whether or not ink exists in the placed ink cartridge.
Also in this case, the detector can be an optical detector comprising a light emission element and a light reception element and the one or more detected parts can each include a prism having one or more reflection faces for reflecting light from the light emission element toward the light reception element.
Further, the one or more detected parts can indicate the information concerning the ink supply section and the prism of each of the one or more detected parts may be formed in a side wall portion of an ink reservoir of the ink cartridge.
Here, one or more of the detected parts can include a gap formed between the one or more reflection faces of its corresponding prism and the side wall portion opposed thereto on an opposite side to the light incidence direction from the detector on the corresponding prism.
Also, the one or more detected parts can be embodied as first and second detected parts. In this case, the first and second detected parts may be placed at different positions along the move passage of the detector in the side wall portion of the ink cartridge placed in the ink cartridge placement section.
Further, the second detected part can include a gap formed between the one or more reflection faces of its corresponding prism and the side plate portion opposed thereto on an opposite side to the light incidence direction from the detector on the corresponding prism.
In doing so, the first detected part can detect the presence or absence of ink in the ink cartridge. Moreover, the second detected part can detect the ink cartridge being placed in the ink cartridge placement section or can detect the type of ink cartridge.
To make it possible to detect the type of ink cartridge, the formation position of the second detected part may be a different position along the move passage of the detector in response to the type of ink cartridge.
Here, if a plurality of ink cartridges, for example, first and second ink cartridges are placed in the ink cartridge placement section, each of the first and second ink cartridges may be formed with the first and second detected parts.
In this case, for example, if a third ink cartridge placed singly in the ink cartridge placement section for use to perform single-color print is included, the third ink cartridge may also be formed with the first and second detected parts, and in a placement state in the ink cartridge placement section, the positions of the second detected parts of the first and second ink cartridges may be made to differ from the position of the second detected part of the third ink cartridge.
In doing so, the type of ink cartridge can be determined based on output of the detector mounted on the carriage and the detection position of reflected light, and whether the print mode is single-color print or multicolor print can be determined based on this determination.
Of course, in the invention, the detector mounted on the carriage may also be a plurality of detectors.
Further, according to the present invention, there is provided an ink jet printer comprising an ink jet head, a carriage mounting the ink jet head and moveable in a print width direction, an ink cartridge accommodating an ink supplied to the ink jet and attached to a ink cartridge holder, an optical detector including a light emission element and a light reception element, and mounted to one of the carriage and a mounting member fixed on a predetermined position, a detected member that can be detected by the optical detector, and the detected member is operable to change its position in accordance with an attached or removed condition of the ink cartridge with respect to the ink cartridge holder.
In the construction described above, the detected member is embodied as a movable type such that the position of the detected member is operable to change in accordance with the attached or removed condition of the ink cartridge. Thus, the attached or removed condition of the ink cartridge can be accurately detected.
Further, it is preferable for providing the detected member with a slidable and/or rotatable feature with respect to the ink cartridge holder. In this construction, the movable detected member is simply constructed to avoid increasing the manufacturing costs associated with the ink cartridge holder.
Still further, the detected member may be urged by an urging member to a first position, and move to a second position by contacting the ink cartridge.